Index: sources/gui/qml/pages/pretreatment/connection/PreTreatmentUltrafiltration.qml
===================================================================
diff -u -ra9b3b248a786b93bf6dfd8c29946d708d18dde9a -refc54445b61a73ccb26aa17714581f12a3154484
--- sources/gui/qml/pages/pretreatment/connection/PreTreatmentUltrafiltration.qml	(.../PreTreatmentUltrafiltration.qml)	(revision a9b3b248a786b93bf6dfd8c29946d708d18dde9a)
+++ sources/gui/qml/pages/pretreatment/connection/PreTreatmentUltrafiltration.qml	(.../PreTreatmentUltrafiltration.qml)	(revision efc54445b61a73ccb26aa17714581f12a3154484)
@@ -33,6 +33,28 @@
 
     header.confirmEnabled: _volumeSlider.isActive
 
+    function reset( vValue ) {
+        if ( ! handleMinimum( vValue ) ) // if not handled go next
+        if ( ! handleMaximum( vValue ) ) // if not handled go next
+        _volumeSlider.reset ( vValue )
+    }
+
+    function handleMinimum( vValue ) {
+        if( _volumeSlider.minimum > vValue ){
+            _volumeSlider.reset  ( _volumeSlider.minimum )
+            return true // handled
+        }
+        return false // not handled so check max
+    }
+
+    function handleMaximum( vValue ) {
+        if( _volumeSlider.maximum < vValue ){
+            _volumeSlider.reset  ( _volumeSlider.maximum )
+            return true // handled
+        }
+        return false    // not handled so check min (if max checked first)
+    }
+
     Text { id: _textLabel
         visible : true
         color   : Colors.textMain
@@ -75,11 +97,24 @@
         ticks   : true
         diameter: Variables.sliderCircleDiameter
         decimal : Variables.ultrafiltrationPrecision
-        minimum : Variables.ultrafiltrationMinDef
+        // it can get the minimum from the message
+        // but some time it has been decided that UI shall always be set to minimum zero.
+        minimum : Variables.ultrafiltrationMinDef // vTreatmentRanges.treatmentRanges_Ultrafiltration_Volume_Min
         maximum : vTreatmentRanges.treatmentRanges_Ultrafiltration_Volume_Max
         minText.font.pixelSize: Fonts.fontPixelFluidText
         maxText.font.pixelSize: Fonts.fontPixelFluidText
         onPressed: isActive = true
+
+        onMinimumChanged: {
+            let mValue = vPreTreatmentAdjustmentUltrafiltrationInit.volume
+            if ( ! _root.handleMinimum  ( mValue ) ) // if not handled go next
+                _volumeSlider.reset     ( mValue )
+        }
+        onMaximumChanged: {
+            let mValue = vPreTreatmentAdjustmentUltrafiltrationInit.volume
+            if ( ! _root.handleMaximum  ( mValue ) )  // if not handled go next
+                _volumeSlider.reset     ( mValue )
+        }
     }
 
     SliderArrows{ id:_sliderArrows